细胞自噬在姜黄素增强LoVo细胞对伊立替康化疗敏感性中的作用

摘要

Objective To study the role of autophagy in the curcumin (Cur) enhancing the chemosensitivity of the colorectal cancer LoVo cells to irinotecan (CPT-11). Methods The LoVo cells were separated into 4 groups:the control group,the Cur group,the CPT-11 group and the Mix group.Western blot assay was applied to determine the expression of autophagy-related protein LC3-Ⅱ and P62. LC3-Ⅱ was detected by immunofluorescence method. Transmission electron microscopy was used to detect the autophagosome. CCK-8 assay was applied to detect the cell growth inhibitory rate of LoVo cells ,which were pre-treated with autophagy inhibitor 3-MA before 24-h treatment of Cur and/or CPT-11. Western blot assay was applied to detect the expression of LC3- Ⅱ and P62. Results The mixed treatment significantly increased the expression of LC3-Ⅱwhile decreased P62 expression,compared with the Cur and CPT-11 treatments. The autophagosomes in cells of Mix group were significantly more than those in cells of the Cur and Cpt group. Pre-treatment of 3-MA significantly reduced cell growth rate in the Cur group,the Cpt group and the Mix group. Pre-treatment of 3-MA significantly decreased the expression of LC3-Ⅱ,while increased P62 expression,compared with the Mix group. Conclution Combinations of curcumin and CPT-11 could enhance the chemosensitivity of LoVo cells to CPT-11,which might be related to the activation of autophagy.%目的:探讨姜黄素(Cur)增强结直肠癌LoVo细胞对伊立替康(CPT-11)化疗敏感性的作用与细胞自噬的关系.方法:选择人结肠癌LoVo细胞按照Cur及CPT-11的不同给药方式,分为对照组(Con)、Cur单药组(Cur)、CPT-11单药组(Cpt)及混合给药组(Mix).Western blot法检测自噬相关蛋白LC3-Ⅱ、P62的表达,细胞免疫荧光法检测LC3-Ⅱ蛋白的表达;透射电镜观察自噬体的形成;自噬抑制剂3-甲基腺嘌呤(3-MA)预处理LoVo细胞之后,CCK-8法检测不同给药方式对细胞24 h生长抑制率的影响,检测LC3-Ⅱ、P62蛋白表达的变化.结果:与Cur、Cpt组相比,Mix组中LC3-Ⅱ蛋白的表达显著上调,P62蛋白的表达显著下调;与Cur、Cpt组相比,Mix组中自噬体明显增多;3-MA预处理后,Cur及CPT-11不同给药方式对LoVo细胞的抑制率显著降低,Mix组LC3-Ⅱ蛋白的表达显著下调,P62蛋白的表达显著上调.结论:姜黄素可增强LoVo细胞对CPT-11的化疗敏感性,其机制可能与激活细胞自噬有关.